1. Field of the Disclosure
This disclosure relates generally to a liner hanger system and methods of setting the same in wellbores.
2. Background of the Art
Wellbores (also referred to as wells or boreholes) are drilled in subsurface formations for the production of hydrocarbons (oil and gas), which are trapped in various zones in the subsurface formations at different depths. A first or uppermost section of the wellbore having a first diameter is drilled to a first depth and such a wellbore is lined with a casing (metal tubular) and cemented to stabilize the upper section of the earth subsurface. A second borehole of a diameter smaller than the first diameter is drilled to a second depth, lined with a casing and cemented. Additional wellbores of successive smaller diameters may also be drilled and lined in the same manner. Once a section is drilled, a liner (also refer referred to as tubular or pipe) is hung from the casing in the prior upper section. A commonly used liner includes a liner hanger on its outside that is set inside the casing to hang the liner in the wellbore. A packer placed above the liner hanger on the outside of the liner is then set to seal the annulus between the liner and the casing above the packer. A commonly used liner hanger is a hydraulically-set device that is in fluid communication with the inside of the service string via communication holes or fluid flow paths in the liner and the service string. A fluid under pressure is supplied to the inside of the service tool to hydraulically set such a liner hanger. The running tool is then disengaged from the inside of the liner and moved to mechanically set the packer. The holes in the liner often create leak paths between the liner and the casing or the formation, which degrade the liner hanger over time. It is therefore desirable to have liner hangers that avoid the use of such holes or fluid flow paths. It also is desirable to set liner hangers and other devices, such as packers, without supplying pressurized fluid from the surface or to manipulate the service string as such operations are time consuming and require using heavy equipment. It is also desirable to obtain information or confirmation that the liner hangers are fully set before releasing the running tools or setting the packers.
The disclosure herein provides apparatus and methods for remotely setting liner hangers without the use fluid flow paths or holes in the liners and other devices, including packers.